TorchHypnosis

Hi, I'm new to this forum, so hello all! I have a 1998 Chevy S10 with 300,000 miles on it. I keep it clean under the hood with engine de-greaser and maintain it using high end lubricants. My concern is that I step on the gas and it has a slight miss and does not accelerate like it used to. It's got a 4.3L V6 Vortec engine. The CEL is not on, and the CAT is not plugged. I recently replaced the spark plugs with NPKs and replaced the wires, and BOTH o2 sensors. Front and rear diff fluids changed regularly, same as engine and transmission lubricants. Truck has been reliable, never had a problem starting or running. Does not leak oil, but burns a bit (not surprising with 300,000 miles on it). It has a slight miss at idle, but when the issue really manifests is when I try and accelerate quickly the miss becomes more obvious and does not gain speed as fast as it used to. I am at a loss. I'm sure my valve stem seals are blowing oil past them, but just a little. Does anyone have any ideas as to why this truck does not accelerate like it used to? Tomorrow I will perform another cylinder compression check, but I did that a few months back when I changed the spark plugs and the cylinders were all within 7 PSI of each other so I'm thinking I still have good compression. Does anyone have any thoughts or ideas as to what may be causing a loss of power with no CEL on? Thanks in advance, and thanks for reading!